*{
   margin:0;
   padding:0;
}
html,body{
    width:100%;
    height:100%;
}
header{
    width:100%;
    height:5rem;
    background:red;
}
footer{
  width: 100%;
  height: 10%;
  background: red; 
  position: absolute;
  bottom: 0;
  display: flex;
  justify-content: space-around;
  div{
      width:23%;
      height:100%;
      background: pink;
      i{
//        width:100%;
//        height:60%;
          display:block;
      }
  }
}
